Can prostaglandin E2 injection improve hair growth?

By Nidhi Saha, BDSNov 9 2022Reviewed by Aimee Molineux

A recent study published in Experimental Cell Research demonstrated that prostaglandin E2 (PGE2) stimulates hair follicle growth. Thus, PGE2 delivery systems could offer a novel approach to managing hair problems and may be an effective strategy for treating hair-related disorders.

Background

Hair loss is a common condition that affects people of all ages. Considering that physical esthetics is an important part of a person’s personality and hair plays a significant role in projecting one’s physical esthetics, hair determines a person's identity. Hence, hair loss may significantly impact an individual’s mental well-being and quality of life. 

Hair loss can be of several types, collectively termed 'alopecia.’ Alopecia can be triggered by various factors and has been categorized as –telogen effluvium, loose anagen hair syndrome, monilethrix, alopecia areata, and chemotherapy-induced alopecia.

There has been ample research on hair regeneration for hair homeostasis––ranging from basic experiments to clinical trials. Current and emerging treatments for hair loss include – finasteride, minoxidil, natural supplements, micro-needling, low-level laser light, platelet-rich plasma, fractional lasers, cellular therapy, and topical prostaglandins. Novel approaches to treating hair loss (HL) include hair tissue engineering and stem cell therapy. 

Prostaglandins are molecular lipid signals derived from arachidonic acid (AA) produced by prostaglandin synthase lysis. PGE2's molecular structure mediates numerous physiological or pathological processes and mediates fever, pain, and inflammation. 

Numerous factors are responsible for regulating hair growth and differentiation; one of these is prostaglandin E2 (PGE2). Experimental studies have shown that radiation-induced baldness in mice can be prevented by PGE2 therapy. 

Therapies that aid in increasing PGE2 levels are minoxidil, castor oil, and omeprazole. The present study examined the impact of the PGE2 matrix on hair growth and hair follicle regulation.

The study

This experimental study entailed designing a PGE2 matrix that conferred positive effects on hair follicle growth at the early anagen phase. The PGE2 matrix was subcutaneously injected into a mouse model of hair loss to evaluate hair gain.

Additionally, the fluctuations of two hair follicle stem-cell markers – Lgr5 and Sox9, and several regulators of hair growth were also investigated. 

Here, a collagen matrix releasing PGE2 was synthesized. To avoid the quick breakdown of PGE2 molecules in vivo, the PGE2 matrix was created by conjugating PGE2 with collagen using crosslinkers. Under various PGE2 matrix treatments, the morphology of hair follicles, the expression of hair follicle stem cell markers, and the hair growth cycle's major regulators were investigated.

Findings

In this study, the properties of the designed PGE2 matrix were first investigated. Hereafter, different PGE2 matrix concentrations were subcutaneously injected into the mouse model. 

The results showed that the PGE2 matrix could transition in situ from a liquid to a gel at normal body temperatures based on its storage modulus and rheological analysis. The synthesized PGE2 matrix promoted hair follicle development in the early anagen phase. 

Notably, excessive PGE2 concentrations rendered lower hair coverage rates. On harvesting the skin tissue sites of PGE2 matrix injection, a higher ratio of developing hair follicles was found that sites with PGE2 injection relative to those with the control sites. Further, PGE2 treatment led to a higher cellular proliferation in the new hair bulbs. In addition, sites with PGE2 matrix injection showed a higher developing hair-follicle ratio.

Further, the variations in expressions of two hair follicle stem cell markers (Lgr5 and Sox9) and a few regulators during the hair growth cycle were investigated. PGE2 could stimulate hair-follicle growth by improving the number of hair-follicle stem cells (HFSCs), such as – Sox9+ and Lgr5+ cells. Furthermore, the new hair follicles with gradually formed outer root sheath structures comprised more Sox9+.

It is known that high bone morphogenetic protein (BMP) signaling in telogen prevents hair-follicle stem cell activation. The accentuating impact of the PGE2 matrix on hair follicles was accompanied by reduced BMP2, especially in the early hair cycle, and beta-catenin activation. 

Conclusion

Thus, the PGE2 matrix could be a potential therapeutic modality for hair growth during early anagen. Yet, further research is warranted on the efficacy of PGE2 matrix injection in treating hair loss and granting hair growth during early anagen. 

A PGE2 delivery system was demonstrated to be an effective therapeutic approach in the treatment of hair problems in the future.